Given a string, find all the duplicate characters which are similar to each others.

Let’s look at the example.
Examples:

Input : hello
Output : l

Input : geeksforgeeeks
Output : e g k s

We can solve this problem quickly using python Counter() method. Approach is very simple.

1) First create a dictionary using Counter method having strings as keys and their frequencies as values.
2) Declare a temp variable.
3) Print all the indexes from the keys which have value greater than 1.

from collections import Counter

def find_dup_char(input):

	# now create dictionary using counter method
	# which will have strings as key and their
	# frequencies as value
	WC = Counter(input)
	j = -1
	
	
	# Finding no. of occurrence of a character
	# and get the index of it.
	for i in WC.values():
		j = j + 1
		if( i > 1 ):
			print WC.keys()[j],

# Driver program
if __name__ == "__main__":
	input = 'geeksforgeeks'
	find_dup_char(input)

Output:

e g k s